Bringing Up Baby

I just finished reading The Seeds Of Life.  It's about the search to find where babies come from.

It might seem obvious to us today, but this was a vexing question that confused serious thinkers and scientists for centuries.  They made lots of guesses (read the book to discover all the bizarre theories that were out there), but they didn't even have a framework for figuring it out.  Remember, they didn't even know that the blood circulated around the body until the 1620s.  You'd think that'd be easy to figure out, but it was a revolution.

As for how babies are created, imagine it's just several hundred years ago, before there were even microscopes.  What sort of evidence can help you?  Well, you know there are men and women, and they have sexual relations and that seems to lead to babies. (Most cultures figured that one out.)

But how is this baby formed, and how does it develop in the womb?  What counts and what doesn't?  Was it preformed, or did it grow into something?  And if it grew, how did it know to do that?  Does the woman supply the baby, or the man?  Is one more important than the other?  What does ejaculate do?  What is the meaning of menstrual blood?

All you can use is logic and observation.  You can look at other animals, and even dissect humans.  But how much does this help you?

Even after the microscope is invented, you've got problems (beyond the numerous biases that people naturally have). Now you can see sperm.  But what do they do?  Are they animals themselves?  How would semen fertilize an egg?  And if you do find an egg--though this isn't easy to do for women, or mammals in general--what does it do?  Does it develop into the baby, or does it just nourish the baby?  Or is it something else completely?

For centuries research zigged and zagged, sometimes moving forward, sometimes rushing into blind alleys.  While physics was making tremendous strides explaining things like the movement of planets, biologists had it rough.

Believe it or not, the answer--that the sperm and the egg fuse to form a single cell which then starts dividing--wasn't discovered until 1875.

I'd recommend the book, which is quite informative and surprisingly funny at points.  It also teaches us not to be too arrogant.  Who knows what tricky questions today will seem obvious in a few centuries?